Elastic thread



Nov. 27, 1934. J, R. GAMMETER 1,982,208

ELASTIC THREAD Filed Sept. 30, 1932 INVE'NTOR 30h11 R. Cromnw'e' E, QM

ATTORNEY Patented Nov. 27, 1934 UNITED, STATES PATENT OFFICE ELASTIC THREAD Application September 30, 1932, Serial No. 635,528

9 Claims.

This invention relates to elastic thread and procedure for making the same.

Heretofore, elastic thread has been made by providing a core consisting of a vulcanized rubber strand upon which is wound cotton, silk or other thread while the core is held under tension. The present invention has for its object the manufacture of a substantially coreless elastic thread comprising coils of cotton, silk, wool or other thread in which the coils are bonded by vulcanized rubber. The thread may be more economically produced by this method and will be a considerable improvement over the elastic core type of thread in that the rubber in the thread is not under initial stress and When the thread is woven or knitted into elastic materials and garments in which it is somewhat stretched, the tension on the rubber in these materials and the degree to which the rubber is stretched when these materials are in service is much less Whereby the rubber has a longer life and the thread or material remains elastic over a longer period of time.

The invention is illustrated in the accompanying drawing and described more in detail below. It is to be understood, however, that the invention is not limited to the specic form thereof shown and described.

Of the accompanying drawing,

Figure 1 is an elevation, partly in section, showing the method of forming the rubberized thread coils for making the elastic thread; v

Figure 2 is an elevation, partly in section, through the thread as it is being made;

Figure 3 is an elevation, partly in section, of the improved thread; and

Figure 4 is an elevation of the thread when stretched and showing the part of the thread Without the rubber incorporated therein to bring out the condition of the thread coils in the stretched thread.

Referring to the drawing, the numeral 10 designates al needle which may be suitably supported at one end as at 11 whereby the other end 12 thereof will be free and unobstructed. On to this needle there is rst closely wound in one direction a thread of cotton, silk, wool or other textile material 13 which may be coated or treated with rubber such as solutionsor water dispersions of rubber prior to winding on the needle, the rubber being partly dry or tacky whereby the windings adhere. Additional rubber may be supplied about and between the windings by passing it through a bore 14 in the needle to the outer end thereof or the thread 13 may be wholly rubberized in this manner without depending upon the pretreatment thereof with rubber. About the wound thread 13 there is Wound in reverse direction a covering thread 15 of the desired textile material, this thread preferably being untreated with rubber but adhering to the tacky, partially dried rubber on the thread 13.

After the thread is thus wound on the needle it may be progressively removed from the needle by slipping it endwise ofi the free end 12 of the 65 needle. This may be accomplished by intermittently pushing the thread off the needle as it is being wound by a reciprocating element 16 having a rounded head 17 about the needle 10, the needle extending through a small aperture 18 70 in the head 17. The element 16 may be reciprocated on a support ll'by suitable means not shown. The windings 13 and 15 are applied under tension and after they pass from the end of the needle contract somewhat as shown in Figure 2.

The windings are laid in laterally abutting helical convolutions so that the pitch of the windings is comparatively low as shown in Figures 1, 2 and 3, whereby the resulting elastic 80 thread is capable of being elongated by stretchmg.

`The rubberized wound thread thus produced is vulcanized in 'any suitable way, preferably Without stretching the thread, as by incorporating vulcanizing ingredients into the rubber with which the thread is treated and subsequently passing the thread through a heated chamber by using an ultra-accelerator in the rubber and curing by aging or treating with rubber in which no vulcanizing reagents are employed and subsequently treating the thread with suitable vulcanizing reagents (cold cure).

As shown in Figure 4, when the thread is stretched the angle of the coils changes, the windings separating and the rubber between the windings being placed under tension. In this wise the improved thread will have a stretch comparable to that of wrapped rubber thread.

While for the sake of effective illustration the drawing shows the thread as quite large, it is to be understood that very flne thread such as that used in knitting may be produced by the invention. The needle 10 may be several thousandths of an inch in diameter and the result- 10b ing thread as shown in Figure 3 may be six or eight thousandths of an inch in diameter.

Modifications of the invention may be resorted to without departing from the spirit thereof or the scope of the appended claims. It will be understood that other elastic` materials similar to rubber, such as elastic gums or resins or synthetic rubbers such as duprene, may be employed instead of rubber. duprene, is not soluble in gasoline or similar clothes cleaning iiuids.

What is claimed isz- 1. An elastic thread comprising a core consisting of a single strand of textile material wound in a helix, the convolutions of which are bonded together by an elastic material.

2. That method for making an elastic strand which comprises winding a helical coil consisting of a single thread laid in laterally adjacent convolutions, said thread being rubberized to bond the adjacent convolutions of the coil together and vulcanizing said strand substantially without tension thereon.

3. That method for making an elastic strand which comprises winding a helical coil consisting of a single thread, winding one or more threads into a coil upon the first coil, said threads being rubberized to bond adjacent windings in each coil together and vulcanizing said strands substantially without tension thereon.

4. An elastic thread structure including a coreless helical coil of closely adjacent parallel thread windings, the windings being bonded toy each other by vulcanized rubber, said windings being of low pitch so that the structure is extensible under tension by separation of the windings and being adapted when stretching tension is released to return to its original closely wound condition.

5. An elastic thread structure comprising la coreless structure including two or more concentric coils of helically wound threads, each coil having close parallel windings bonded together by vulcanized rubber and said coils being bonded to each other by vulcanized rubber, said windings being of low pitch so that the structure is extensible under tension by separation of the windings of the respective coils and being adapted Certain of these, such aswhen stretching tension is released `to return to its original closely wound condition.

6. That method for making an elastic thread structure which comprises winding without the use' of a core a helical coil of rubberized thread so that the windings are substantially transverse to the axis of the coil and relatively close to each other, and vulcanizing said thread to bond 'the windings together.

7. An elastic thread comprising a helical coil composed of a single strand of material, the adjacent convolutions of which are tree to move axially apart and are treated with rubber and vulcanized whereby the adjacent convolutions of the coil are bonded to each other by the vulcanized rubber, said coil being capable of elongation when put under tension by separation -of the convolutions and by stretching of the rubber between convolutions.

'8. An elastic thread comprising an inner helical coil composed of a single rubberized strand wound in laterally abutting convolutions in one direction, and an outer helical coil of a single strand wound about said inner coil in the opposite direction in laterally abutting convolutions, the adjacent convolutions of the respective coils being free to separate in an axial direction, the convolutions of each coil being bonded together by the rubber and the two coil units being bonded together by rubber whereby each coil may elongate under tension by the spreading apart axially of its convolutions and by stretch of the rubber between convolutions.

' 9. An elastic thread comprising a helical coil consisting of a single textile thread wound in a series of adjacent convolutions of such proximity that the coil is of relatively low pitch, said convolutions being bonded together by vulcanized rubber whereby the coil may be elongated by axial separation of the convolutions and by stretching of the rubber between convolutions.

JOHN R. GAMME'IER. 

